Researchers have devised a technique that allows a computer to create three-dimensional images of famous landmarks, by combining numerous two-dimensional photos of those landmarks from Internet photo sharing sites such as Flickr.

For the Building Rome on a Cloudless Day project, 3 million photos of Rome were accessed online, and used to produce 3D images of all the city’s major landmarks. Utilizing commodity graphics hardware, it took a single PC less than one day to accomplish the task.

The project is the work of a combined team from the University of North Carolina(UNC) at Chapel Hill and the Swiss ETH-Zurich. They were also able to create 3D images of landmarks in the city of Berlin.

While programs such as Microsoft’s PhotoSynth already perform a similar function, the new system is said to be much more powerful.

“Our technique would be the equivalent of processing a stack of photos as high as the 828-meter Dubai Towers, using a single PC, versus the next best technique, which is the equivalent of processing a stack of photos 42 meters tall – as high as the ceiling of Notre Dame – using 62 PCs,” said team leader Jan-Michael Frahm, of UNC. “This efficiency is essential if one is to fully utilize the billions of user-provided images continuously being uploaded to the Internet.”